Vehicle door constructions typically feature a metal door frame with a sheet metal outer panel or skin that defines the door's exterior and an inner sheet metal panel secured to the door frame. Various door components, including window regulator rails, audio speakers, latches, and the like, are fastened in openings defined in the inner sheet metal panel. Covering the inner door panel is a removable trim panel that provides an aesthetically pleasing facade viewed by occupants seated in the passenger cabin of the motor vehicle. Typically disposed between the inner sheet metal panel and trim panel is a water and/or sound barrier that closes the various openings and prevents water infiltrating the interior of the door from wetting the interior surface of the trim panel. A wire harness communicates electrical connections between mechanisms attached to the vehicle door and controls on the trim panel. The latch is connected by a cable to an inner release handle accessible to the vehicle occupant.
Door trim panels have previously been constructed as assemblies in which the individual components are assembled together and attached to a panel by several different conventional processes including adhesives, heat staking, sonic welding, fasteners, etc. Such assemblies may include a nibbed armrest sub-assembly consisting of an injection molded skin that is assembled with a substrate. The nibbed armrest and substrate sub-assembly is then directly attached to the trim panel or attached to a removable bolster covering an access opening in the trim panel. While such conventional assemblies may provide a desired appearance and functionality, the use of such conventional assemblies introduce their own drawbacks. For instance, the use of a separate substrate to reinforce and support the nibbed armrest introduces a separate component in the assembly and also increases cost.
What is needed therefore is a door trim panel construction that addresses these and other deficiencies of conventional door trim panel constructions.